/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.wagon.providers.ssh.knownhost;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringReader;
import java.util.HashSet;
import java.util.Set;

import org.codehaus.plexus.util.IOUtil;
import org.codehaus.plexus.util.StringOutputStream;
import org.codehaus.plexus.util.StringUtils;

/**
 * Provides known hosts from a file
 *
 * @author Juan F. Codagnone
 * @since Sep 12, 2005
 */
public class StreamKnownHostsProvider extends AbstractKnownHostsProvider {

    public StreamKnownHostsProvider(InputStream stream) throws IOException {
        try {
            StringOutputStream stringOutputStream = new StringOutputStream();
            IOUtil.copy(stream, stringOutputStream);

            stream.close();
            stream = null;

            this.contents = stringOutputStream.toString();

            this.knownHosts = this.loadKnownHosts(this.contents);
        } finally {
            IOUtil.close(stream);
        }
    }

    protected Set<KnownHostEntry> loadKnownHosts(String contents) throws IOException {
        Set<KnownHostEntry> hosts = new HashSet<>();

        BufferedReader br = new BufferedReader(new StringReader(contents));

        String line;

        do {
            line = br.readLine();
            if (line != null) {
                String tokens[] = StringUtils.split(line);
                if (tokens.length == 3) {
                    hosts.add(new KnownHostEntry(tokens[0], tokens[1], tokens[2]));
                }
            }

        } while (line != null);

        return hosts;
    }
}
